#!/usr/bin/node

const user ={
  name:'刘志伟',
  age:'21',
  qq:'2055572879',

};

const log = console.log;
//三种占位符
log('name: %s', user.name);
log('age: %d', user.age);
log('JSON: %j', user);

log('qq: %s', user.qq);

log('qq: ', user.qq);

log('qq:'+ user.qq);
log(`qq:${user.qq}`);

console.error('Error! something wrong!');
